定向井、水平井和斜井的概念是20年前发展起来的,当时只有苏联做过一些有限的试验。海上钻井开展后,在70年代,斜角只有45～50°。1970年,美国阿可油气公司打了一口60.96m 的排放斜井,转方位半径小于9.1440m。1979年,该公司采用了一种新的井下造斜工具,打了一口斜井,花费50万美元,相当于普通井两倍的成本,但在井深、方位控制上尚存在问题。同年,加拿大一家公司采用一种井架倾斜45°的钻机,在只有79.248～201.168m深的油砂地层中打了3口倾角为90°浅斜井。由于后 The concept of directional wells, horizontal wells and inclined wells was developed 20 years ago when only the Soviet Union had done some limited tests. After offshore drilling commenced, the bevel angle was only 45-50 ° in the 1970s. In 1970, the United States 阿可 oil and gas company hit a discharge 60.96m inclined shaft, turning radius of less than 9.1440m. In 1979, the company adopted a new downhole beveling tool that cost $ 500,000 to incline an offset well, doubling the cost of a normal well but still having problems with well depth and azimuth control. In the same year, a Canadian company used a 45 ° derrick rig to drill three shallow inclined wells with 90 ° inclination in an oil sand formation of only 79.248 to 201.168 m depth. Because after